The Mk.8 Naval Gun is located on the Bow of the Type 21 Frigate: https://edmundfovargue.artstation.com/projects/q9VaEn
This is a model of the original "mod 0" version of the Vickers 4.5 Inch (114mm) Mark 8 Naval Gun, with a rounded fibreglass gun housing that was used during the 1982 Falklands War. It was used on pretty much every modern Royal Navy warship with a main gun from 1972 till today (with most ships now using the modern "mod 1" aka "Kryten" version).
My model of the Mk.8 comes in at 1,680 Triangles with 993 Vertices and has a single 1024 x 1024 texture (although textured in 4096 x 4096)
Some ships also had an Antenna mounted on the top of the gun housing (mainly the Type 21’s without Exocet launchers but also the HMS Bristol, etc) and I've made this version for future-proofing purposes, even if my Type 21 Frigate doesn't need it. The Antenna adds an additional 22 Triangles to the gun, bringing the total to 1,702 tris, and the textures are included in the main sheet.